Hi everyone,
I am working on an Arduino project where I need to have a slide sensor that is flexible. I have done some prototypes and started with the SoftPot Membrane Potentiometer, which uses resistance values to determine the linear location you are touching on the sensor. This has worked well, but it has some downfalls in that you need a good amount of force for the sensor to detect you are touching it. Because of this, it is very easy to accidentally not press hard enough while using the sensor in an action.
I started experimenting with capacitive sensors, but have hit a dead end with that so far. I was using the CapSense library (Arduino Playground - CapacitiveSensor), a 2K resistor and a 3.3M resistor (just what I had). While I was able to sense touching, I would ultimately need many of these along a strip to detect linear position, by simply detecting which sensor you trigger.
Unfortunately, when getting to a large amount of sensor strips, I need 2 pins per strip. That would mean for just 5-10 sensors, I would need 10-20 pins (which is too many, and too much wire).
I understand this is projected capacitance, not surface capacitance. Unfortunately it is very difficult for me to find info on surface capacitance since it is a very generic term. I would prefer to have a sensor at each end of the strip, and when moving closer to one it can determine that you are closer to one or further from the other, thus providing a relationship that could be linearized to determine position...
Any good ideas? I am willing to fab my own PCB or generally experiment. The best solution would be an off the shelf sensor similar to the SoftPot but with capacitive capabilities to enable touch sensing
Thanks guys!